Basic Thermal Power Plant Chemistry, for Operational Staff.
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Understand the basics of Water Quality Control to avoid the scale corrosion and biological growth in the Power plant system, and to operate the mentioned at max performance.
Understand the troubleshooting events to the plant chemistry system
Basic Thermal Power Plant Chemistry, for Operational Staff.
1. Power Plant Operator
Chemistry Training.
Prepared By : -
Syed Aqeel Ahmed
M.Tech, Chemical, MBA, G.M.
Stagger In-Charge
Chemistry & Environment
Hub Power Station, Pakistan,
Hub Power Service Ltd,
Hub Power Company Ltd.
2. At the end of the respective training course, the participants will
be able to:
• Understand the basics of Water Quality Control to avoid the scale
corrosion and biological growth in the Power plant system, and to
operate the mentioned at max performance.
• Understand the troubleshooting events to the plant chemistry system.
Main Objective
3. External Water Treatment
• It is the removal of impurities from water out side the (
Condenser ) in power plant because raw water taken
from open sea that contain a large number of impurities
with respect to surrounding , so it is very necessary to
make cleaned and purify the water before it entrance
to wards (Condenser/boiler)
7. Manual dosing regime, in absence of
Electro chlorination Plant
• Each cane contain 30 kgs of 15%
NaO’Cl concentration.
• Dosing half cane every after six
hour in each bay.
8. External Water Treatment
Practically all surface water contain small
amount of mud, clay ,silt ,decayed, vegetation,
Micro Organisms etc.
To obtain required quantity of water
various techniques are applied Such as
Clarification ,Filtration ,Evaporation ,Softening,
Desalination (MED, MSF & RO ) , Ion
Exchange.
9. Thermal Desalination, MED
Multi-Effect distillation (MED) is a
water desalination process that distill
sea water by flashing a portion of the
water into steam in multiple stages.
The strict control of operation
parameters plays vital role for
availability of MED.
Anti scalant chemical Belgard-EV is
being used to maintain 4 ~ 6 ppm in
feed water.
10. Demineralization
Removal of all kind of ion from water by ion exchange is
called demineralization. Any salt dissolved in water
consist of two types of ions, +Ve ion called cat ion and
-Ve ion's called anion . In demineralization process cat
ion and anion present in water are removed one after
other by organic ion exchange resin
The organic resin's are of two types
Strong Cat ion resin R-HSO3 Sulphonic group
Strong anion resin R-NH3OH Amino group
11. Cat ion Exchangers
Strong Cat ion
A regenerated strong cat ion resins has
sulphonic functional group (-HSO3) and
removes cat ions, from water as given
below.
2RSO3.H + CaSO4 (RSO3)2 Ca+H2SO4
2RSO3.H + CaCl2 Strong Acid
2RSO3.H + Ca(NO3)2
2RSO3.H + Ca(HCO3)2
(RSO3)2 Ca+2HCl
(RSO3)2 Ca+2HNO3
(RSO3)2 Ca+2H2CO3 Weak Acid
The water at the outlet of strong cat ion exchanger cat
ion strong acids ( HCl , H2SO4 , & HNO3 )
12. Anion Exchanger
Strong anion
This filter remove anion of both weak acids and strong acids.
(RNH3)2CO3 +2H2O
(RNH3)2SiO3 +2H2O
RNH3Cl +H2O
(RNH3)2SO4 +2H2O
2RNH3.OH + H2CO3
2RNH3.OH + H2SiO3
2RNH3.OH + HCl
2RNH3.OH + H2SO4
Alkali Treatment
NaOH is used passed through the filter.This filter is stopped for
regeneration when SiO2 content increasing trend.
13. Mix Bed Filter
The filter bed contain strong cat ion The cat ion and
anion resin are so intimately mixed that water following
through the bed may be considered to have comes
across a large number of small strong cat ion and
strong anion beds. The water at the outlet of mix bed is
of higher quality purity and its conductivity may be low
as 0.05 µS/cm.
Increase in silica content of effluent water
of the mixed bed is a signal of exhaustion of strong
anion resin and increase of conductivity means
exhaustion of cat ion resin.
14. REGENERATION OF CATION & ANION EXCHANGER.
When all the H ion of the cation exchanger and when all the
hydroxyl OH ion of the anion resin are consumed in
removing cation & anions from the water, the resin will no
more remove cation & anion from water, then it is said to
have exhausted.
The cation’s exhausted resin are replaced by H ion of the
acid (HCl) the exhausted anion resin is regenerated with
sodium hydroxide (NaOH) to make it useful once again.
RSO3. Ca + 2HCl → RSO3. H + CaCl2
RNH3. Cl + NaOH → RNH3. OH + NaCl.
15. SPECIFIC CONDUCTIVITY
Tomaintain conductivity levels within
acceptable limits.
Tofacilitate the correlation of a water chemistry
parameter (e.g.,pH, conductivity, ammonia correlation).
Tocheck the accuracy of water chemistrycontrol (such
as ammonia orpH).
Towarn of condenser tube leakage/seepage.
Towarn of condensate polishermalfunction.
16. Conductivity: Meter
Measuring the conductivity is an
accurate way to determine salinity.
Conductivity of ions is measured using the
following two units…
Freshwater = micro Siemens (µS)
Saltwater = milli Siemens (mS)
17. Troubleshooting High Purity Conductivity Measurements
Symptom Possible Cause—Corrective Action
Grab sample conductivity reads
higher than on-line sample
Grab sample is exposed to air too long, allowing significant
absorption of CO2.—Seal grab sample better or measure from
flowing sample.
Grab sample sensor and/or container are contaminated.—
Rinse longer.
Portable instrument has inadequate temperature compensation.—
Use on-line instrument type as portable.
Grab sample conductivity reads
lower than on-line sample
Portable instrument has inadequate temperature compensation—
Use on-line instrument type as portable.
Conductivity reads high or off-scale DI Resin beads or fines are trapped between sensor electrodes—
Clean sensor.
Instrument has inadequate temperature compensation.—Check
setting, replace instrument.
Conductivity reads low or cycles
down and up
In makeup water, gas bubbles form in the sensor due to pressure drop,
temperature rise and/or CO2 release. When bubbles are large enough,
they dislodge and new ones begin to form. Repetition of this causes
cycling.—Increase flowrate and/or relocate sensor into more turbulent
flow to carry away bubbles.
In makeup water system, sensor is located in or after a “deadleg” which
is very slowly rinsed after regeneration.—Revise piping.
Cable between instrument and sensor is too long— limit length to
system specifications.
Instrument has inadequate temperature compensation.—Check
setting, replace instrument.
18. SIGNIFICANCE OF pH MONITORING
• Tomaintain pH levels within acceptablelimits.
• Corrosion of metals and alloys is a functionof pH.
• AlkalinepHvalues increasethestabilityof the oxide
film and reduceoxidesolubilityinwater.
• Tofacilitate the correlation between two or more water
chemistry parameter (e.g., pH, conductivity, ammonia
correlation).
• Toprovide a feedback signal forautomated
chemical dosing and processcontrol.
• Towarn of in-leakage ofcontaminants.
• Towarn of condensate polishermalfunction
19. Measuring pH
Using a meter
“Calibrate the probe and meter according to the
manufacturer’s directions. Use of two buffers (pH 7
and 9) for calibration is recommended.”
20. Internal Water
Treatment
The term internal water treatment describe
the reaction induced with in the boiler
system to render the water less harmful to
system operation .
The main features of internal
water treatment are summarized on the
next slides.
21. Internal Water Treatment
Prevention scale by
1) Ether precipitating chelating the hardness in water
2) Maintaining the sufficient alkalinity for appropriate
chemical reaction.
3) Sludge conditioning to keep the suspended particle in
non adhering state.
4) Maintaining total dissolve solid with in limit.
Prevention of Corrosion.
In Boiler by
1) Scavenging oxygen formulation of protective film .
2) Maintaining sufficient alkalinity neutralizing CO2
formulation of protective film.
22. Oxygen Scavenger
An oxygen scavenger is a chemical which
remove dissolve O2 in H2O by a reduction reaction and
there by inhibits to corrosion cause by the O2.
23. Hydrazine
Hydrazine ( N2H4 ) can economically remove
small amount of dissolved oxygen . In addition it acts to
produce nitrogen and water thereby leaving the TDS
level of water un effected.
N2H4 + O2 N2 + 2H2O
Theoretically 1ppm of hydrazine is required to
react with 1ppm dissolved “ O2 “ but actually 1.5 to 2.0
ppm of N2H4 are required per 1ppm “ O2”
Hydrazine also react with Fe2O3 in the boiler
water to form a passive magnitide film on the boiler
internal surface preventing form the corrosion.
N2H4 + 6Fe2O3 4Fe3O4 + N2 + 2H2O
25. Treatment for Condensate line
Neutralizing Amines
Volatile or
neutralizing amines are employed
as corrosion inhibitors to prevent
Co2 corrosion . They neutralize
carbonic acid and raise
condensate pH . Volatile amine
are
1) Ammonia NH3
2) Cyclohexyl amine C6H11NH2
3) Morph line C4H4ONH
26. Neutralizing Amines
These amine are injected to
the feed water .The amine added to the
feed water volatizes together with the
steam generated in the boiler with the
condensation of steam . The amine
neutralizes Co2 to raise pH of condensate
and thereby inhibits corrosion .
NH3 + H2O
C6H11NH2 + CO2+ H2O
C4H8ONH +CO2 + H2O
NH4+HCO3
C6H11NH3+HCO3
C4H8ONH2+HCO3
27. Filming Amines
These represent an effective
economical approach to condensate
system corrosion control.
The purpose of filming amines in
the formation of an adherent mono
molecular film providing protection from O2
and Co2 corrosion . First the film is build up
then only the amount of amines is required
to maintain the film .
28. Typical Filming Amines
1) Octa decyl amine
2) Hexa decyle amine
CH3(CH2)16 CH2NH2
CH3(CH2)14CH2CH2
3) Di Octa decyle amine CH3 (CH2)16(CH2)2NH2
The general formula for filming amine is
R-NH2 where R= Alkyl group ( C10 – C12 ) the
corrosion inhibits . The effect of filming amines
on the steel material increases proportionally
with the increased number of carbon atoms.
The amines when feed in the boiler ,
also volatize with steam and condense to form
an organic film in condensate line .
29. AFTER CATION COLUMN CONDUCTIVITY(ACCC
Themeasurement wasadopted for
monitoring the power plantsteam
/ water cycle asit candetect low levels
of anion contaminantssuch as
chlorides, sulphates, and organic acids
(parts per billion) on acontinuous
basis,while at the sametime the
measurement is very simple and easy
to maintain.
30. REACTIVE SILICA
Tomaintain silica levels within acceptablelimits.
Towarn of in-leakageofcontaminants.
To facilitate the correlation of a water chemistry parameter
with plant operating variables, with an aim to optimizing
operations.
To check the accuracy of water chemistry control (for silica),
so ensuring that carry-over and deposit rates are kept at
acceptablelowlevels.
Towarn of condensatepolishermalfunction.
31. HYDRAZINE
Hydrazine is monitored in mixedmetallurgyfeedwater cyclesusing reducingAll VolatileTreatment
-AVT(R).Itis monitoredintheplantforthefollowing reasons:
Tomaintain hydrazine levelswithin acceptable limits.
Toevaluation of other chemistryparameters (i.e., ORP
anddissolvedoxygen).
Toprovidefeedbackstimulusforautomated
processcontrol.
32. CHLORIDE
Elevatedchlorideconcentrationsintheboiler canlead tocorrosiveconditions
which candamage thewater walltubes.
Towarn of in-leakage of contaminants(primarily condenser
coolingwater ingress).
Tofacilitate the correlation with other chemistry
parameters (i.e., cationconductivity).
Tocheckthe accuracyof water chemistry control (for chloride), so
ensuring that carryover and deposit rates are kept at acceptable
lowlevels.
Towarn of condensatepolishermalfunction.
Towarn of make-updemineralizermalfunction.
33. PHOSPHATE
Phosphateisa CoreMonitoring Parameterforboilers with Phosphate
Treatment.It ismonitoredintheplantforthefollowing reasons:
To maintain phosphate levels withinacceptable limits.
To checktheaccuracyof water chemistry control(suchas
thesodium-to-phosphatemolar ratio).
To facilitatethecorrelation ofphosphate
contentwith plant operatingvariables.
To warn of in-leakageofcontaminants.
34. AMMONIA
Ammonia is monitored to:
Checktheaccuracyof water chemistrycontrol,so
ensuringthat corrosionratesarekeptat
acceptable lowlevels.
Facilitatethecorrelationof ammonia with
otherchemistry parameters(i.e.,pHand
specific conductivity).
35. SODIUM
Sodiumis aCoreMonitoringParameter.It should bemonitored
continuously on-line to checkthe acceptabilityof water chemistry,
therebyensuring that corrosionratesarekeptat low levels.
Tomaintain sodium levels within acceptablelimits.
Towarn of in-leakage ofcontaminants.
Towarn of boiler watercarryover.
Toidentify cooling water in-leakage at the mainsteam
condenser.
Towarn of condensate polishermalfunction.
36. DISSOLVE OXYGEN
Tomaintain dissolved oxygen levelswithin
acceptable limits.
Tocheckthe accuracyof water chemistrycontrol,
so ensuring that corrosion rates are kept at
acceptable low levels.
Tofacilitate the correlation of a water chemistry
parameter with plant operating variables, withan
aim to optimizing operations (e.g., condenser air
removal or de-aeratoroperations).
37. IRON AND COPPER
Iron and copper areanalyzed periodically tomeasure corrosion
product levels in the steam-water cycle.Corrosion product
monitoring in the plant is conducted primarily for thefollowing
reasons:
Tofacilitate the correlation of a water
chemistry parameter with plantoperating
variables.
Tocheckthe accuracyof water chemistry
control (such as reducing agent, oxygen,
ammonia or pH),so ensuring thatcorrosion
rates arekeptat acceptable lowlevels.
38. CONDENSER LEAKAGE
A potential major source of ingress of
impurity into the boiler water system is from
leakage of cooling water into the main
condenser steam space (because steam
space is maintained by vacuum) which is
called condenser leakage.
39. DETECTION OF CONDENSER LEAKAGE
Online sodium increases (normal < 2 ppb). After
cation conductivity increases (normal <0.2
µS/cm.
Chloride ion will go on increasing and can not be
controlled with out operation of CBD.
Condensate, Feed train and in Boiler Drum, Total
Hardness may also appear and increase after
approximate 5 ppm Chloride ion, (in sea water
cooled condenser).
40. PREVENTIVE/REMEDIAL ACTION
1. Open CBD10 0 %, makeup will go high. (Heat as well as
DM water loss).
2. Increaset he concent rat ion of Sodum Hydroxide and free
alkalinity in boiler.
3. Limit/close as for as possible the boiler de-
superheater spray water to prevent contamination of
the system.
4. Isolate one pat h of condenser, and see the results
and vice versa.
5. Put CPU into service if available.
41. LEAK LOCATION
If the leak is in minor in nature:
In running units, isolate one half the condenser
at a time and monitor the chemical parameter s
and find out which half is leaking. Isolate the
leaky half por tion. Plug or repair the leak .
Normalize and comeback to full load.
42. LOCATING THE SPECIFIC LEAK
• First is path detection
• Flood test
• Candle Test
• Dye test
• Foam Test
43. CONDENSATE POLISHING UNIT
Condensate polishing is employed to
purify the return steam condensate in
order to meet the quality requirements of
high pressure thermal cycles and
minimize consumption of make-up
water.
44. BENEFITS OF USING CONDENSATE POLISHING UNITS.
• Improvement in the quality of condensate and cycle clean-up.
• Reduce blow down and mak up requirement,
• Improvement in Boiler water quality for Drum type Boilers.
• Quick start-up and as a result full load condition are reached
early giving economics.
45. 8H
FI
PI
FIA
*
* LL * LL
L
* LL
* L * L *
*
TEMPPRESS
CTRL
WATER TANK
VENT
TO ROOF
O.C.E C.E
MAKE-UP
( DEMIN )
STATOR WATER SYSTEM
SWS1.DRW
FI
FSA
PA
PC
FA
TI
TR
DP
QSA
PI
*
FLOW INDICATION
FLOW ALARM
FLOW ALARM EMERG
PRESS INDICATION
PRESS ALARM
PRESS CONTROLLER
DIFF PRESSURE
TEMP INDICATION
TEMP RECORDER
ACTION
CONDUCTIVITY MONITOR
ALARM OR INDIC TO CCR
CENTRIFUGAL
PUMPS
STOP CHECK
VALVES
QSI CONDUCTIVITY INDIC
RESIN
BED
FSAFSA
FI
FSA
QIA
*
DP
TR
TR
TA
FA
TI TR TR
*TA
TSA
TSA
QIAY
TR
DV
DV
TI
PI
PA
CTRLFI
DP
DP
PC
PCPI
TI
TR
TR
TA
FIA
PA PA
TSA ***
*
LA
PI QAI
LA
PI
H2 INLET VALVE
H2 OUTLET VALVE
AIR INLET TO STATOR WATER TANK FROM SLMS
1 2
1
2
SAMPLE INLET TO SLMS
SAMPLE OUTLET FROM SLMS
DRAIN VALVE # 2
EXISTING DRAIN VALVE # 1
AIR OUTLET VALVE #1
AIR OUTLET VALVE # 2
O2
DO2 SENSOR TO SLMS
FROM SLMS
35
33
31
32
34
18
17
52. Chemical waste water control
(without boiler washing water).
Chemical waste water control by WWTP by using HCl &
NaoH maintain water PH from 6 to 9
• Chemical washing wastes arising from operation and maintenance activities
will be collected via an installed drains network and transferred to the Waste
Water Treatment Plant. The treated effluent, suitable for disposal, will be let into
the CW outlet.
53. Boiler washing Chemical waste water
control
• Boiler washing Chemical waste water also control by WWTP with
clarification unit by using NaoH & coagulant & separated sludge
collect in sludge bed & then dump into the control waste.
54. WASTE WATER TREATMENT
Task of Chemical Drain in Retention Basin, Boiler & GAH
Wash Water Effluent from Storage Pond to maintain and
eliminate:
a) Suspended solids
• Metals
b) Coloids – substances of:
• variable size
• variable charge
Methods of pretretment:
Direct separation – sedimentation, filtration, ultrafiltration or
microfiltration
Coagulation and separation – ultrafiltration, nanofiltration or reverse
osmosis
Clarification (coagulation + flocculation -sedimantation) – acid, neutral and
alcalic
55. ClaRification of feed water
Clarification is composed of:
• coagulation - elemination of particle charge
• flocculation - formation of flakes and their sedimentation
• sedimentation (filtration) – separation of the flakes
Clarification depends upon pH value of the water – different techiques:
• Acidic clarification
• Neutral clarification
• Alkaline clarification
Acidic clarification (pH < 7)
Fe3+(coagulant) + 3 HCO3
- = Fe(OH)3 + 3 CO2 at pH 5.5 – 7.0
Neutral clarification (pH= 6 -8)
Clarification agent: coagulant + NaOH = neutral flakes
Alkaline clarification (pH >10)
Fe3+(coagulant) + 3 HCO3
- = Fe(OH)3 + 3 CO2
2 CO2 + Ca(OH)2 = Ca(HCO3)2+ Ca(OH)2 = 2 CaCO3 + 2 H2O
56. ClaRification of feed water
Floculation
• Speed of floculation – concentration of sediment x imput of energy (mixing) x tim
• Two stages of floculation
- perikinetics phase (Brown motion of particles)
- ortokinetics phase (mixing or other agitation)
Sedimentation
• Separation of flake in sediment cloud
Filtration
• One – component sand filters
• Multi-component sand filters
57. Gas Air Heater
Water Wash Water
Economiser
Wash Water
Wash Down
Sump
Storage
Pond
Clarifier Tank
Sludge Beds Sump
Retension Basin
Demin Effluant Aux. Blr. Drains
Demin Basin
Sump
Ph Adjustment Tank
Discharge To Sea
Coagulent
Recirculation If Ph Not in limits
Chemical Injection Balance
Mixer
Mixer
Ph Feedback
Caustic
Caustic
Pumps
Pumps
Pumps
Waste water System
Simplified Drawing
58. LS
FROM NaOH STORAGE TANK
OIL SEPERATION
& OIL YARD DRAIN
CHEMICAL DRAIN
AUX BOILER
DRAIN
REGENERATI
ON
DEMIN BASIN SUMP RETENTION BASIN+ PUMPS
No 1 NaOH
DOSING
TANK
COAGULANT
DOSING TANK
No 2 NaOH
DOSING
TANK
HCL
DOSING
TANK
P.H. ADJUSTMENT
TANK
SLUDGE DRYING BEDS
SUPERNATAN SUMP
& PUMPS
OPENGULLEY
STORAGE POND
& PUMPS
CLARIFICATION
PACKAGE UNIT
EFFLUENT PUMPS
LS LS
FROM HCL STORAGE TANK
LS
WASTE WATER TREATMENT PLANT
10% Ferric
Chloride
pH controlled
LS LS
GAS AIR
HEATER
WASHING
WATER
No 1 WASHDOWN
SUMP & SUMP PUMPS
PUMP
CONTROLS
LS LS
GAS AIR
HEATER
WASHING
WATER
No 2 WASHDOWN
SUMP & SUMP PUMPS
PUMP
CONTROLS
PUMP
CONTROLS
L
LS LS
& SUMP PUMPS
PUMP
CONTROLS
LS P
P
PUMP
CONTROLS
L L
L
LSLS
PUMP
CONTROLS
PUMP
CONTROLS
59. 8
4
6
Hub Power Station
27
7
8
19
42
3
5
13a 13a
14
20
20
29
29
13
13
13 13
12 12 12 12
1
1c
11
9a
45
10
15
38 22
26
24
23
23a
2
17
3737
30
31
18
RISING STATION CHEMICAL
WATER
DRAINS LAYOUT
16 16 1616
1b
21
21
21
21
21a
32
33
29a29a
36
46
34
1a
44
39
47
9
RS1
0
Building Sources
1-T.G building # 12.
2-Chemical store building # 18.
3-Hydrogen building # 11
4-Stack building # 14..
5-Control/D.G building # 30.
6-Demin drain basin. building # 5.
7-Aux.-boiler building # 10.
8-Chlorination building # 1.
..
7
RS-09
RS0
8
RS-21 RS-20 RS-19 RS-18
Cond Pit Cond Pit Cond Pit Cond Pit
RS-17
RS-16 RS-15 RS-14 RS-13
Foul Water Foul Water Foul Water Foul Water
RS-22
Note: Rising station #13 to #16 & #18 to #21
are not the chemical water drain but discharge is connected
with RS #10. The layout is provided just for taking an idea.
Shift C Shahid Ansari
60. 8
4
6
Hub Power Station
27
7
8
19
42
3
5
13a 13a
14
20
20
29
29
13
13
13 13
12 12 12 12
1
1c
11
9a
45
10
15
38 22
26
24
23
23a
2
17
3737
30
31
18
RISING STATION
OILYWATER
DRAINS LAYOUT
16 16 1616
1b
21
21
21
21
21a
32
33
29a
29a
36
46
34
1a
44
39
47
9
Building Sources
1-T.G building # 12.
2-Transformers building #16.
3-Workshop building # 24.
4-F.O metering building # 32...
5-Control/D.G building # 30.
6-Boilers. building # 13..
7-Aux.-boiler building # 10.
8-F.O transfer building #19..
9-Unit F.O pump building # 20.
10-F.O Service tanks building # 28..
7
RS-06
RS-17
RS-22
RS
07
RS-05
RS-01 RS-02 RS-03 RS-04
4MKC 3MKC 1MKC2MKC
4BAT
4BBT 3BBT
3BAT 2BAT
2BBT6BCT 5BCT
1BAT
1BBT
Shift C Shahid Ansari
61. 8
4
6
Hub Power Station
27
7
8
19
42
3
5
13a 13a
14
20
20
29
29
13
13
13 13
12 12 12 12
1
1c
11
9a45
10
15
38 22
26
24
23
23a
2
17
3737
30
31
18
RISING STATION SEWAGE
WATER
DRAINS LAYOUT
16 16 1616
1b
21
21
21
21
21a
32
33
29a29a
36
46
34
1a
44
39
47
9
RS-11
RS-12
Building Sources
1-T.G building # 12.
2-Switch yard building # 23.
3-Workshop building # 24.
4-Admin building # 26.
5-Control building # 30.
6-Aux. Elec. building # 37.
7-Re-boiler building # 38.
7
RS-22
RS-17
Shift C Shahid Ansari
62. World Bank Guidelines - Reporting of Releases
Parameter Limit & Sample Point
BOD No limit quoted Sewage plant discharge .
pH Between 6 and 9 Waste water plant final discharge.
Suspended solids 30mg/l discharge - taken as difference
across the cooling water inlet and outlet
Cooling water intake and effluent of
WWTP effluent discharge,
Sewage plant discharge.
Temperature Max. 3°C increase across Inlet and Outfall
Cooling water intake and Outfall
Temperature at Hubco Marina.
Oil & Grease 20mg/l Waste water plant discharge
Chlorine 0.2mg/l Ave 0.5mg/l MAX. Outgoing Cooling water
at discharge plume (b)
T.D.S <10% Increase across Cooling water Inlet and
Outfall Cooling water intake and outfall.